1. Technical Field of the Invention
This invention relates to radio telecommunication systems and, more particularly, to a system and method in a radio telecommunications network for secondary traffic charging.
2. Description of Related Art
In radio telecommunications networks, a wide variety of services such as voice, video, data, and image services are available to subscribers. In using these radio telecommunications networks, the most precious resource is the radio spectrum. To maximize the effectiveness of the networks, code division multiple access (CDMA) has been developed to facilitate communications involving a large number of system users. There are other multiple access communication system techniques, such as time division multiple access (TDMA) and frequency division multiple access (FDMA), however, the spread spectrum modulation technique of CDMA has proven to offer many advantages over the other methods.
In a CDMA system, a unique binary spreading sequence, known as a code, is assigned for each call to each user. Multiplied by the assigned code, the user's signal is spread onto a channel bandwidth wider than the user signal bandwidth. The ratio of the system channel bandwidth to the user's bandwidth is known as the "spreading gain." All active users share the same system channel bandwidth frequency spectrum at the same time. The signal of each user is separated from the other users' signals at the receiver by issuing a correlator keyed with the associated code sequence to "de-spread" the desired signal. In this manner, an increased number of simultaneous users can be served.
In addition to serving an increased number of users, the existing CDMA system supports variable rate service. The variable rate service enables the CDMA system to reduce interference when a user is in the low rate transmission mode. Additionally, when the CDMA system is not at a full rate of transmission, other types of services, called secondary traffic can be transmitted simultaneously.
There are disadvantages in the existing system. First, although the CDMA system is capable of providing secondary traffic services, there is no method or system to charge the subscriber for these additional services. Additionally, there is no way to charge the subscriber a different rate for using the secondary traffic services than what the subscriber is charged for primary traffic services.
Although there are no known prior art teachings of a solution to the aforementioned deficiency and shortcoming such as that disclosed herein, prior art references that discusses subject matter that bears some relation to matters discussed herein are U.S. Pat. No. 5,416,797 to Gilhousen et al. (Gilhousen), U.S. Pat. No. 5,442,625 to Gitlin et al. (Gitlin), and U.S. Pat. No. 4,204,093 to Yeh (Yeh).
Gilhousen discloses a system and method for communicating information signals using spread spectrum communication techniques. The system and method provide for generating signal waveforms in a CDMA cellular system. The system uses pseudonoise modulation sequences that provide orthogonality between the users in order to reduce mutual interference and allow better link performance. However, Gilhousen does not teach or suggest a method or system for the charging of secondary traffic services.
Gitlin discloses a multi-code division multiple access system allowing a user at a radio transmitter to dynamically change its source data bit rate. Thus, Gitlin describes a method to provide variable data rate in a CDMA network. In response to a user input selecting a plurality of source bit rates, an adjustable coding device spreads and transmits the user's digital information received at the selected bit rate to a channel bit rate which at least equals the highest bit rate of the plurality of source bit rates. Thus, Gitlin merely describes a method of supporting variable rate service in a CDMA system. However, Gitlin does not teach or suggest a method or system for counting or reporting the number of frames having secondary traffic. Additionally, no method or system is disclosed for the charging of the secondary traffic services.
Yeh discloses a method for using a communication system to provide variable data rate service in a time-division multiple access (TDMA) network using super frames and sub-frames. The system disclosed by Yeh provides for a technique using a plurality of different frame rates for the individual receiving stations or areas in a TDMA communication system which is dependent on the traffic demands between the various pairs of remote stations or areas making up the communication system. However, Yeh does not teach or suggest counting or reporting the number of frames, and does not disclose a method or system for the charging of secondary traffic services.
Thus, it would be a distinct advantage to have a system and method for the charging of secondary traffic services to a subscriber in a radio telecommunications network. It is an object of the present invention to provide such a system and method.